The herbal and pharmaceutical industries should invest more time and resources in studying herb-drug interactions, suggest researchers in the UK, who found 'a widespread lack of interest' in this area from both industries.
The researchers, from the Peninsula Medical School in the UK, say that millions of people take herbal and conventional medicine together. Interactions between the two should be addressed, as certain herbal supplements, such as St John's wort, are thought to cause potentially dangerous side effects when taken with some prescription drugs.
The team carried out a survey, by sending questionnaires to the heads of research and development at the top 14 herbal supplement makers and the top 30 pharmaceutical companies worldwide.
Questions asked whether drug-herb interactions were considered important and whether the companies were conducting studies into those interactions. The survey also asked whether funds were specifically set aside to study the topic, and if so, how much of the 2000 research and development budget was allocated.
Only 15 companies (34 per cent) replied fully to the questionnaires. Another five responded but did not fill out the survey completely, and 24 did not respond at all, writes Dr Joanna Thompson Coon, a research fellow in the complementary medicine group at Peninsula, in this month's Archives of Internal Medicine.
Of the 15 companies who responded, 67 per cent considered herb-drug interactions to be important, but only three manufacturers said they had conducted studies, and only two regularly allocated funds to such research. Both herbal companies, these two set aside 5 and 6 per cent respectively of their research and development budgets for the studies.
"Knowing that millions of patients take herbal and conventional medicine concomitantly, often without the knowledge of their physicians, and considering our present lack of understanding of herb-drug interactions, more systematic research into this area seems a matter of urgency," concluded the team.